Physical Environment

The physical environment programs on the Site C project monitor air quality, water quality, climate, and noise to protect the health of people, wildlife and fish populations in the region. These programs last throughout the project's construction phase and some go well into dam operations.

Air Quality Monitoring

We have a large network of five air quality stations and seven meteorological (climate) monitoring stations throughout the Peace River valley, from Hudson's Hope in the west to Taylor in the east.

The air quality monitoring stations contain instrumentation to measure one or more of the following:

  • Smoke and pollen particulate matter (PM2.5)
  • Dust particulate matter (PM10)
  • Exhaust: nitrogen dioxide (NO2), sulphur dioxide (SO2) and carbon monoxide (CO)
  • Wind speed and wind direction are also measured to determine the source of the contaminants

These stations are placed in a climate-controlled trailer, with instrumentation on the roof (air quality measurements) and tower (wind speed/direction).

 
Air quality monitoring station recently installed in Hudson's Hope in October 2020. It will be in place throughout the construction of the shoreline protection berm and the first two years of Site C operations.

BC Hydro has a data sharing agreement with the provincial government and all the air quality data collected by the project is publicly available. The Ministry of Environment and Climate Change audits our station to ensure high quality and reliable readings. Air quality advisories and measurements are posted online. 

Site C contractors are required to mitigate the effects on air quality from their activities. Measures could include:

  • Adjusting drop heights when loading materials onto vehicles and into stockpiles
  • Using dust suppressant on construction roads and material extraction areas
  • Minimizing idling of vehicles and equipment.

BC Hydro has implemented an automated alert system to notify contractors when real-time air quality is approaching provincial ambient air quality limits at any of our stations, so that they can review their worksite and take immediate action.

Noise Monitoring

Construction of a project like Site C can be noisy, with heavy equipment, truck and rail traffic, and power generators. We require Site C contractors to mitigate the noise from their activities, through measures such as:

  • Maintaining all equipment in good working order
  • Scheduling construction activity near homes at times that will reduce the period of disturbance
  • Maintaining or building acoustic barriers (e.g. vegetation, berms)

When we receive a complaint about noise, we work with residents to address their concerns. Often, simple things such as moving a generator, or making sure construction is only taking place during agreed-upon work hours, can resolve the issue. Sometimes, we install noise monitoring equipment to better understand the issue.

Water Quality Monitoring

BC Hydro monitors extensively throughout the Peace region to assess the effects of Site C construction on water quality and quantity. This includes programs on groundwater (e.g. drinking water well monitoring) and surface water (e.g. construction water discharges to the Peace River).

We monitor water discharged from Site C work areas to make sure it meets provincial regulations on turbidity and acidity. To comply with regulations, contractors take measures such as:

  • Creating sediment ponds for settling
  • Using flocculants, a clarifying agent to treat water and improve sedimentation
  • Applying CO2 bubblers to neutralize pH of concrete wash water

We maintain a network of in-river probes to measure turbidity and water temperature. This helps us to understand the conditions in the river and assess effects downstream on municipal water wells and industry water intakes.

We work with local municipalities on a program to sample and test the water at the water wells for the City of Fort St. John and District of Taylor and in the Peace River on a quarterly basis. We also work with well owners within one kilometre of the future Site C reservoir to monitor their water quality. We'll test the well before and after reservoir inundation, to assess potential impacts on their well.

Water treatment 

Site C construction sometimes results in run-off water that needs to be treated before it reaches the Peace River.

Once example is when we excavate into shale rock that, due to its geochemical properties, could generate acid runoff when exposed to air and water over time. This naturally-occurring phenomenon, known as acid rock drainage and metal leachate (ARD/ML), can be sped up through construction activities that disturb and uncover potentially acid-generating (PAG) shale. The shale would then leach minerals and metals into the environment as surface water runs over the exposed rock.

We're taking steps to mitigate this ARD/ML risk by compacting and covering PAG shale materials in specified disposal areas. We also line ditches with limestone riprap to buffer water quality.

Sometimes, these steps are not possible – such as when slopes are too steep to cover before the onset of acid rock drainage. In these cases, we collect poor quality water that has contacted the exposed PAG at an onsite treatment facility. We designed a mobile water treatment facility specifically for the Site C project. Poor quality water is brought to the pre-treatment collection pond by piping or vacuum truck. After the water has been treated to raise the pH and remove metals, it's taken to another settling pond before being released to the Peace River.

Throughout this process, we monitor water levels, flow rates and water quality (e.g. turbidity, pH, and concentrations of metals of concern, including cadmium, cobalt, copper, zinc). The Site C project has water quality limits that apply at the discharge points.

Climate Monitoring

The Site C climate monitoring stations supplement the air quality stations, and measure precipitation, air temperature, relative humidity, and soil moisture. This information then informs things such as agricultural monitoring commitments and engineering design. This network adds to BC Hydro's existing climate monitoring stations, which help us to operate the WAC Bennett and Peace Canyon dams.

Learn more